For months, Tanya Husser left the doors and windows of her Mandeville home unlocked night and day in hopes that her brother, who authorities say escaped from a Covington work-release facility in late 2010, would show up and end her worrying.

But Billy Husser never appeared at her door and never called any of his relatives.

In the 3 ½ years since the 42-year-old inmate vanished from the Northshore Workforce facility, investigators told the family, there’s been no recorded activity on his credit cards or any use of his Social Security number, his sister said.

The last time anyone saw Husser was on Dec. 29, 2010, at the controversial work-release program that Sheriff Jack Strain shut down two months ago, partly in response to a recent flurry of other escapes.

Staff said Husser was in his bunk at a 3:30 a.m. bed check, according to a St. Tammany Parish Sheriff’s Office incident report. At 8:30 a.m., Husser’s employer, Heavenly Ham in Covington, called to say he had not shown up for work, the report said, and a count was taken that verified he wasn’t at the facility. At 11:30 a.m., an investigator with the Sheriff’s Office arrived.

Capt. George Bonnett, a spokesman for the Sheriff’s Office, said there is nothing new to report in relation to the investigation, which he described as “still very much an open case.’’ The Sheriff’s Office and the state Department of Corrections consider it an open fugitive investigation.

Tanya Husser said the authorities made no effort to get word out to the public at the time of the escape. She learned that her brother was gone two days after he disappeared.

“A couple of weeks later someone else got out, and he was plastered all over the TV,’’ she said. “Why isn’t my brother on TV?’’

The family is desperate to know what happened to Billy Husser, who struggled with depression and alcohol abuse, according to his sister. The 42-year-old was incarcerated for violating the terms of his probation on a third-offense DWI.

Husser, who visited and talked to her brother often, finds it hard to believe he would run away after spending a year in the program. “He was looking forward to getting out, starting his life over,’’ she said.

According to the state prison system, Husser was scheduled to be released on May 5, 2011.

His sister also has trouble understanding how he could have left the work-release facility without anyone noticing. When she visited him at the facility, she said, alarms would go off if anyone even touched a side door.

Strain shut down the program in March, the same day that another inmate, Christopher Ricker, escaped from the facility, allegedly kidnapping and raping his ex-girlfriend during his flight to Tangipahoa Parish. His was the third escape in a short period of time, and it followed weeks of reporting by The New Orleans Advocate and WWL-TV on lax oversight at the facility.

But while the Covington facility had the highest number of escapes in the state in 2013, Husser is the only one in the history of the facility who was not later apprehended, according to the Sheriff’s Office.

Tanya Husser describes her brother as a troubled person who had one suicidal episode. She doesn’t believe he belonged in jail but thought he was safe in the work-release facility. Now she doesn’t believe the facility did its job in watching the inmates, she said.

Department of Corrections Secretary Jimmy LeBlanc has called revelations about Northshore Workforce “an embarrassment to us all,’’ but he said no red flags showed up in inspections conducted there in 2011 and 2012.

State Inspector General Stephen Street is investigating the program, and LeBlanc said he plans to write new regulations that will require any Louisiana sheriff who wants to privatize a work-release program to go through a bid process first.

Strain didn’t do that with Northshore Workforce, which was run by a group of political supporters, or the recently privatized program in Slidell, St. Tammany Workforce Solutions.

For Husser’s family, though, such measures come too late.

“It’s hard not knowing where he is, knowing if he’s dead or alive, if he has a blanket to sleep on or a pillow,” Tanya Husser said. “He’s missed a lot in my family.’’

Every time she sees a homeless person, she feels compelled to look to see if it is her big brother.

“Billy is the type who would have called to say, ‘I’m OK,’ ’’ she said tearfully. “That’s all we need. Just an ‘OK.’ ’’

Follow Sara Pagones on Twitter at @spagonesadvocat.